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Counter weights keep sliding

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#1 wxcloud

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Posted 30 March 2020 - 07:43 PM

Ok, a bit of an issue with the EQ 6 R pro I didn't really notice until recently, my counter weights seem to have problem staying where I put them, I've had one slide down onto the one under it, I can't seem to make them tight enough and almost to the point I think the screw tip might break of I tighten much more...

Is this another simple issue I'm missing? Do I need to turn the bushing inside the counter weights where the screw does NOT go through the hole but rather push up against the bushing?

I can see where one or both decide to slip during a slew and just cause a bit of an issue.

#2 TrustyChords

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Posted 30 March 2020 - 08:22 PM

Yeah, I know what you mean. First, make sure the counterweight shaft is nice and free of any grease or moisture.

 

Also I crank these weights down really fairly hard. I'm not sure if I'm over doing it, but they stick for me. Sometimes I'll even tighten with two hands once it is already fairly tight. The weight on the bottom I put more attention to, since mine are stacked together.

 

Another thing, which may be superstition on my part, but I've found they hold better if you put the weights on so that the screw part is more toward the top, vertically speaking.



#3 TOMDEY

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Posted 30 March 2020 - 08:27 PM

That's a catastrophe just waiting to happen! At least it's just a little scope. Fix it right away. It's prudent/essential to provide two entirely independent means to hold your counterweights (each and every one) where intended. My scopes are big and my counterweights are heavy (100 pounds each not uncommon)... so I get nervous about such blunders.    Tom

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#4 greenstars3

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Posted 30 March 2020 - 09:30 PM

Get some o-rings and place them under the weights to prevent their movement.

Will not degrade function nor value or cause any harm.

 

Robert

 

edit: Tom, nice scope 


Edited by greenstars3, 30 March 2020 - 09:33 PM.

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#5 AhBok

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Posted 31 March 2020 - 02:28 AM

The screw should go through the hole in that plastic spacer. I tighten mine by hand as tight as I can. I use 3-12lb weights and they stay in place. I wouldn’t worry about breaking that very large bolt as long as you tighten by hand and fight the urge to reach for your vise-grips!
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#6 JOEinCO

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Posted 31 March 2020 - 04:47 AM

.....Do I need to turn the bushing inside the counter weights where the screw does NOT go through the hole but rather push up against the bushing?.....

I am not familiar with the EQ6R's counterweights, but you mention a bushing. By bushing do you mean compression ring? Is the design like the female end of a diagonal, where the set screw acts on a compression ring instead of the set screw pushing directly on the eyepiece? 

 

If that's the case, most certainly have the screw push against the bushing. 

 

Can you post a picture of the center bore of one of your counterweights?



#7 macdonjh

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Posted 31 March 2020 - 09:05 AM

wxcloud,

 

It's perhaps OCD on my part, but I keep my counter weights close together, so they are touching.  I started that years ago so dew didn't collect on every counter weight surface, and I've been doing it ever since.  I've had the same problem from time to time when it gets cold at night.  I figured the counter weight shaft was contracting enough to make the weight's bolts loose.  So I started, on cold nights, tightening the counter weight bolts an hour or so after I initially set up.

 

I like greenstar3's suggestion about an o-ring, I was going to suggest a hose clamp, but that may be a hassle if you have to put your mount up and take it down every night.



#8 Raginar

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Posted 31 March 2020 - 10:03 AM

Get a wrench if you're having trouble tightening them by hand.  It won't take a ton of effort.

 

Chris


Edited by Raginar, 31 March 2020 - 10:03 AM.


#9 EFT

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Posted 31 March 2020 - 02:34 PM

Make sure that the point that presses on the bar is also clean.  Something else you can do is use some sandpaper to wrophen the surface around the circumference of the bar (i.e., not in the direction of the bar length) so that the knob point has something to grip on.  



#10 wxcloud

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Posted 31 March 2020 - 07:06 PM

Thanks all, will keep looking into things, may resort to using bread ties and toothpicks as shims for now. Or maybe a rubber band at the end of the stack.

I think the tip of the screw has a nylon finish.

#11 MikeECha

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Posted 01 April 2020 - 06:29 AM

Thanks all, will keep looking into things, may resort to using bread ties and toothpicks as shims for now. Or maybe a rubber band at the end of the stack.

I think the tip of the screw has a nylon finish.

As AhBok said on post 5. If the screws does not press against the bar directly, the cw will slide. That happened to me. Make sure the scres goes thru the hole on the bushing. Otherwise it will not hold the cw in place.


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#12 wxcloud

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Posted 20 April 2020 - 07:58 PM

Haven't had much of a chance to try solutions for the sliding counterweights as I haven't gotten out much.

Last outing, I did crank down on the screws and that didn't really work, actually almost got my fingers into a counterweight sandwich :o

I did have a couple other ideas, one was to just take out the plastic bushings all together and maybe the friction of the paint will keep it in place as well as a slight angle. Not sure this will help. The other idea is to get either masking tape or gaffers tape and make a couple thin layers for the end of the thumbscrews to indent or bite into to keep things more in place. Would also serve as reference for ball park setting up.

I don't think this would leave a residue but if so, shouldn't be too much of a issue to clean up.

#13 Epox75

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Posted 20 April 2020 - 09:21 PM

You could scratch a bit the bar surface where you lock the counterweight, it's going to happen anyway. I am saying that because now that my bar is 8 years old and the counterweight grips way better on the part I use more, scratched, than other parts of the bar, unscratched. Maybe the sandpaper still could make it too even or scratch away more than you need, I would use the point of a nail or a knife



#14 Gazpacho

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Posted 21 April 2020 - 03:08 AM

Get 2 part shaft collars. I keep a set with my Orion Sirius Pro. Once I get the weights where I want them, a shaft collar goes on above and below each weight. I don't trust the weight screw to hold more than 5 minutes. The shaft collars will hold forever. Also called a 2 piece clamp collar.

The following link is just for illustrative purposes.

https://www.zoro.com...ASABEgKeXvD_BwE
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#15 wxcloud

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Posted 21 April 2020 - 10:50 AM

A quick update, set up a bit light last night so only used one weight, I removed the plastic bushing out of it and it seemed to have held better or at least had a firmer bite. Took a bit more force to actually make the weight move once it was screwed down.

Will keep tinkering with things.

#16 Stricnine

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Posted 30 June 2020 - 04:30 PM

Bringing up an older thread, but my EQ6R-Pro has been having this same issue starting over the last 6 months or so.  I've had the mount since late 2018, and is used frequently.

 

I could always tell when I was going to have a weight slide, based on the way the screw felt as pressure was applied to it.  If it felt suddenly almost impossible to turn/tighten then it was virtually 100% guaranteed that the weight was going to slide, trying to tighten further by hand was not possible.  When the screw tension increased smoothly as tension was applied it would not slip.

 

I removed the screws from the weights and could see that the threads had been ground down and a fine grey powder was all over them and inside the weights.  Cleaning the the grey powder from the threads and blowing it out of the weights didn't help.  The weights, in my case, are slowly destroying the screw threads.  The tip of one is a lot more mashed/thin compared to the other (one weight was used a lot more before adding another heavier telescope required use of both weights), and is the most problematic weight.

 

I cleaned the counterweight shaft, the screw tips, and still it would slide.  I removed the bushings and cleaned the inside of them out a little while ago (< 10 minutes) and, so far, they aren't sliding any more.  But time will tell.

 

I suspect that the counter weight screws probably need to be replaced on mine at the very least.  I also suspect the threads in the weights are also worn down too.  How much that's contributing to the slipping?  No idea.


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#17 Stricnine

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Posted 30 June 2020 - 04:52 PM

Here are what the screw threads/tip look like:

1st (most used) screw (has the most trouble with slipping, and has the sudden stop when tightening):

Screw 1 Threads

Screw 1 Tip

 

2nd (somewhat less used) screw:

Screw 2 Threads
Screw 2 Tip

 


Edited by Stricnine, 30 June 2020 - 04:53 PM.


#18 EFT

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Posted 30 June 2020 - 08:25 PM

The nylon tips are going to need to be replaced at the very least.  You can purchase a piece of nylon rod and cut small pieces to replace them.  Brass also works.  The threads generally aren't going to cause the sliding problem but they clearly show that you a placing a lot of torque on the knobs, way too much.  However, if the threads have become cross threaded that could cause you to not be able to tighten the knobs.  There is no way that you should have to put so much torque on the knobs to either damage those threads or the nylon tips.  Those weights are punny compared to many others.  That is way too much wear on the tips and the threads.  It should never be difficult to tighten the knobs.  That would suggest that something was keeping you from actually tightening the knobs and as a result the weights slipped.

 

I would recommend going to this website:   Look for either knobs with nylon or brass tipped studs that are long enough or build one from the parts that they have (i.e., knobs and studs).  The only potential problem is whether or not you can use a threaded stud all the way through the counterweight.  If not, then you might have to be creative by tapping out the rest of the hole or drilling out the hole and threading it to a larger size.  You are going to need to at least clean out the current threads with a tap.



#19 Jarno

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Posted 02 July 2020 - 05:16 AM

Some of the more expensive counterweights have a separate brass pin that's pushed against the shaft by the screw. It seems that something like that would be easy enough to DIY.

 

Jarno



#20 wxcloud

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Posted 02 July 2020 - 11:27 AM

Oh, kind of forgotten about this thread. Mount use has been few and far between :( I did however find a potential high tech and very expensive option for this issue... Masking tape! :o it's sloppy for sure but the few times I have tried it, seems to work. The screw grabs the tape a bit and if it slides some, tape bunches up and acts like a stopper.

I simply ran a couple a couple 1" wide strips down the counterweight shaft and also removed the plastic bushings from the weight.

It's sloppy, ugly and so far works, I can replace tape fairly easy. I am uncertain if residue will accumulate but nothing a razor won't scrape off. Gaffer tape might work also.

#21 Jarno

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Posted 03 July 2020 - 12:25 PM

No no no no no, that won't do at all. Obviously you should've used duct tape! Ya know, just to keep the myth alive. Or maybe not even bother with the screws but just duct tape the weights to the shaft... Anyway, good to hear you got it sorted out.

 

Jarno



#22 Nippon

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Posted 03 July 2020 - 06:15 PM

I have the same problem with a Skywatcher 11 pound counterweight I use on a Vixen GPD2. I found lubricating the threads of the lock bolt helped allowing the bolt to be tightened more easily. In contrast the Vixen counterweights I have do not use a nylon tip and lock solid with just a slight snugging. The weights for my GM8 have Delrin tips and also lock solid but they have 3/8" lock bolt with a metal T handle. 



#23 Michael Covington

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Posted 03 July 2020 - 06:41 PM

The nylon tips are going to need to be replaced at the very least.  You can purchase a piece of nylon rod and cut small pieces to replace them.  Brass also works.  The threads generally aren't going to cause the sliding problem but they clearly show that you a placing a lot of torque on the knobs, way too much.  However, if the threads have become cross threaded that could cause you to not be able to tighten the knobs.  There is no way that you should have to put so much torque on the knobs to either damage those threads or the nylon tips.  Those weights are punny compared to many others.  That is way too much wear on the tips and the threads.  It should never be difficult to tighten the knobs.  That would suggest that something was keeping you from actually tightening the knobs and as a result the weights slipped.

 

I would recommend going to this website:   Look for either knobs with nylon or brass tipped studs that are long enough or build one from the parts that they have (i.e., knobs and studs).  The only potential problem is whether or not you can use a threaded stud all the way through the counterweight.  If not, then you might have to be creative by tapping out the rest of the hole or drilling out the hole and threading it to a larger size.  You are going to need to at least clean out the current threads with a tap.

What web site is that?



#24 Stricnine

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Posted 03 July 2020 - 07:05 PM

What web site is that?

Probably pushing his website linked in his signature.



#25 collaredkeeper

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Posted 03 July 2020 - 09:33 PM

Shaft collars work great too, just need to match to your shaft diameter. 

https://www.globalin...mission-collars

 

AOUeuyj.jpg


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